A laser oscillation cooling device (100) includes a light emitting section (1) that emits laser excitation light (Z1), a laser excitation section (2) that excites the laser excitation light (Z1) to emit laser light (Z2) and has a heat generating region (S) where heat is locally generated, a storage tank (3) capable of storing an extremely low temperature liquid (L), a pressurizing section (31) that brings the extremely low temperature liquid (L) into a sub-cool state by pressurizing the inside of the storage tank (3), and a jetting supply section (4) that removes heat from the laser excitation section (2) by jetting the extremely low temperature liquid (L) in the sub-cool state from a plurality of jet ports arrayed in a two-dimensional manner to the laser excitation section (2).